I followed the discussion there, and I second Wolfgangs opinion that authoring systems should not create exceptions to correct for flaws in wacky ingest/playout routines.

However, in this case it is not so easy, because the 'missing' tag, although optional, would not be considered an exception or sideway. One wouldn't need a checkbox 'make Doremi compliant' or whatever, but just add a tag that is optional and DCI/SMPTE compliant.

Of course, Doremi should still fix this bug in their player. Then the question is again, do we help this bug getting fixed if authoring systems are made 'bug compliant' and less people yell at Doremi to fix it?

Aside from that, I found a download link to the old evaluation version of Doremis Cineplayer in the above mentioned thread, and it actually works on my outdated 10.6.8 C2D MacBook. It can not keep up with full speed 2k playout, but it's enough for a quick check into a DCP at reduced resolution, at least it works better than VLC.
There are more choices for windows players, but on older Macs, this seems to be a useful option.

Another question - wouldn't normally incorrect/invalid file hashes prevent manual editing of DCP files? Of course, it would again be the job of the ingest/playout routine to detect them. I assume cinema servers would do that, but have no idea wether and why software players would?